Topic: Something new and interesting for F2/F3 engines!

[Don R]

I've gotten the go ahead and use it line. It's easier to accept if they will say why it's OK to go ahead and use it, but most reps don't want to explain anything.

[MRieck]

 A hole at the bottom of the boss is a better drain hole than a fill hole secondary to gravity. Vertical channels empty better than fill unless they are under pressure.
 The horizontal hole takes oil off the wall (which is plentiful) and pushes it toward the pin on the downstroke.
 Oil mist will hit the pin itself and provide more lubrication then it hitting that tiny hole and trying to "force" it to overcome gravity.
 The old Earl's catalog had a line that basically said if you try to defy physics you are doomed to failure.
 

[HondaMan]

A hole at the bottom of the boss is a better drain hole than a fill hole secondary to gravity. Vertical channels empty better than fill unless they are under pressure.
 The horizontal hole takes oil off the wall (which is plentiful) and pushes it toward the pin on the downstroke.
 Oil mist will hit the pin itself and provide more lubrication then it hitting that tiny hole and trying to "force" it to overcome gravity.
 The old Earl's catalog had a line that basically said if you try to defy physics you are doomed to failure.
 

That's a keen point about the availability of the oil on the cylinder walls, and very true. It would also be under considerable pressure on the downstroke, especially at high RPM.

"M", you mentioned above about piston skirt tapers also being part of the equation: do you also have any text or articles or anything that may cover it in some detail, rules to follow, effects of, etc.? The inquiring Engineering mind (here) wants to know more...